The traffic sign you mentioned is known as the Lane sign - without oncoming traffic with an integrated sign indicating 2-lanes in the direction of travel and 1-lane in the opposite direction.

This sign indicates that the road ahead has two lanes going in your direction, accommodating more vehicles and allowing for overtaking. It also specifies that there is a single lane in the opposite direction. This setup is often found on roads where there is a need to improve traffic flow in one direction while maintaining a lane for oncoming traffic.

Drivers should adhere to the marking provided by this sign, ensuring they stay in the appropriate lane and are mindful of oncoming vehicles. Always check mirrors and signals before changing lanes, especially in a situation where there may be oncoming traffic in the opposite lane.